Feature Request: Deleting bookmarks from bookmark button

(Where do feature requests belong to? If there is not yet, I would also request a dedicated place to manage for feature requests)

Platform: Windows, OS X, Linux desktops

Description:
The bookmark popover menu should contain a button to remove the currently opened website from bookmarks.

Use case:
When unintentionally clicking on the bookmark button (instead of somewhere next to it), a bookmark is created. To keep your bookmarks in order, you may want to undo the bookmarking. However clicking again the bookmark button does not remove the bookmark, and the bookmark popover menu does also not contain a button to delete the unwanted bookmark. The only way I see is to open the opera:bookmarks in a new tab, searching for the same website as in the previous tab and unbookmarking it.